In 2013 I was lazy at demo recording (mostly due to being distracted by some other spheres), but still like a few of my past-year records:

M209S550 -- inspired by VDGG's words: "At least we know now that NM100 is impossible :-)".C423S226 -- such a lovely megawad deserves more skill-5 attention.BS03-337 -- it was tempting to beat all three digits of Krypto's 4:58 UV Max record.BS03N213 -- BSelfish MAP03 is cool for Nightmare racing as well.

__________________Here are my latest Doom speed demos, and here is the archive of my records done in 2005-2016.

Easiest: Dark Resolution 2008 map02 uv-max - I played the map once, watched Anima's run and then beat it on the first try.
Hardest: Darkwave 32 uv-max - Very tricky level for me and even more tricky to max. Was so happy to just reach the exit.
Most fun: Hell Revealed 1943 uv-max - Cool BFG spam map with funny visuals\music.
Most daring: Hell Revealed 2 map03 uv-max - at first I didn't believe that I could beat Belial. :)
Most grindy: Community Chest 4 map01 uv-max - but j4rio topped me here later.
Most frustrating: Speed of Doom map11 uv-max - low hp, needed luck in many many parts to survive.
Most archaeological: Hellcore map15 uv-max - very obscure wad among speedrunners for various reasons, I even had to edit the map to make it playable in prboom+.

Most of my demos are fairly short speed/pacifist demos, and I have a hard time determining the ones that really stood out for me, but here's a few I can think of:

hardest nomo: Map 32 of Alien Vendetta was very hard at the time to get 27 on. A lot of my Kama Sutra demos were recorded this year, and they're my favorite nomo demos, but I'm still waiting to release them.

most fun TAS: No Chance UV-Max - nice to get under 10 minutes max here.